WOOD-DERIVED CARBOHYDRATE COMPOSITION

Abstract

A wood-derived carbohydrate composition is disclosed. The wood-derived carbohydrate composition comprises C6 monomeric sugars and C5 monomeric sugars in a total amount of at least 80% by weight relative to the total dry matter content of the carbohydrate composition. The ratio of C5 monomeric sugars to C6 monomeric sugars is at most 0.15. A process for producing a wood-derived carbohydrate composition is also disclosed.

Description

Description Title of the invention: CARBOHYDRATE-DERIVED COMPOSITION WOOD technical field

[0001] This disclosure relates to a carbohydrate composition derived from hardwood comprising C6 monomeric sugars and C5 monomeric sugars. Furthermore, this disclosure relates to a process for producing a wood-derived carbohydrate composition. Context

[0002] Various processes are known for converting a raw material of biological origin, such as lignocellulosic biomass, into a liquid stream of various sugars. The ability to provide a sufficiently pure carbohydrate composition with properties suitable for other applications, such as the production of monoethylene glycol or ethanol, remains a challenge for researchers. Summary

[0003] A wood-derived carbohydrate composition is disclosed. The composition may comprise C6 monomeric sugars and C5 monomeric sugars in a total amount of at least 80% by weight relative to the total dry matter content of the carbohydrate composition. The ratio of C5 monomeric sugars to C6 monomeric sugars may be at most 0.15.

[0004] A process for producing a wood-derived carbohydrate composition is also disclosed. The process may include: the supply of a wood-based feed load from a raw material based on wood and including wood chips, and the fact to subject the wood-based feed to pretreatment for to form a slip: ii. the separation of the slip into a liquid fraction and a fraction comprising solid cellulose particles through a first se- solid-liquid preparation to form a fraction comprising particles of solid cellulose having a total dry matter content of 15 to 50% weight, in which the first solid-liquid separation process includes washing the fraction containing solid cellulose particles up to the quantity of soluble organic components in the fraction comprising solid cellulose particles, from 0.5 to 5% by weight relative to the total dry matter content; iii. Optionally, the dilution of the separated fraction comprising particles of solid cellulose up to a total dry matter content of 8 to 20% weight ; iv. subjecting the fraction comprising solid cellulose particles to an enzymatic hydrolysis to form a hydrolysis product, in which the fraction comprising solid cellulose particles has a total content in dry matter of 8 to 20% by weight; and v. the separation of the hydrolysis product into a solid fraction comprising lignin and a liquid fraction of carbohydrates by a second se- solid-liquid preparation to recover the liquid fraction of carbohydrates as that composition of carbohydrates derived from wood. 1. A wood-derived carbohydrate composition obtainable by the process as disclosed in this specification is further disclosed. Brief description of the drawings The attached drawing, which is included to facilitate understanding of the embodiments and forms part of this specification, illustrates one embodiment. The drawing shows: Figure [Fig.1] presents a flowchart of one embodiment of the process for producing a carbohydrate composition derived from wood. Detailed description A carbohydrate composition derived from wood is disclosed. The carbohydrate composition may include C6 monomeric sugars and C5 monomeric sugars in a total amount of at least 80% by weight relative to the total dry matter content of the carbohydrate composition, in which the ratio of C5 monomeric sugars to C6 monomeric sugars is at most 0.15. In addition, a process for producing a wood-derived carbohydrate composition is also disclosed. The process may include: the supply of a wood-based feed load from a raw material based on wood and including wood chips, and the fact to subject the wood-based feed to pretreatment for to form a slip: ii. the separation of the slip into a liquid fraction and a fraction comprising solid cellulose particles through a first se- solid-liquid preparation to form a fraction comprising particles of solid cellulose having a total dry matter content of 15 to 50% weight, in which the first solid-liquid separation process includes washing the fraction containing solid cellulose particles up to the quantity of soluble organic components in the fraction comprising solid cellulose particles, from 0.5 to 5% by weight relative to the total dry matter content; iii. Optionally, the dilution of the separated fraction comprising particles of solid cellulose up to a total dry matter content of 8 to 20% weight ; iv. subjecting the fraction comprising solid cellulose particles to an enzymatic hydrolysis to form a hydrolysis product, in which the fraction comprising solid cellulose particles has a total content in dry matter of 8 to 20% by weight; and v. the separation of the hydrolysis product into a solid fraction comprising lignin and a liquid fraction of carbohydrates by a second se- solid-liquid preparation to recover the liquid fraction of carbohydrates as that composition of carbohydrates derived from wood. 1. A wood-derived carbohydrate composition obtainable by the process as disclosed in this specification is further disclosed. In one embodiment, the wood-derived carbohydrate composition obtainable by the process as described in this specification is the wood-derived carbohydrate composition as described in this specification. That is, the wood-derived carbohydrate composition described in this specification can be produced by the process described in this specification. The term "liquid carbohydrate fraction" can refer to a liquid fraction comprising (soluble) carbohydrates. The liquid carbohydrate fraction can be recovered in the process as described in this specification as a wood-derived carbohydrate composition. The wood-derived carbohydrate composition described in this specification refers to a composition that includes carbohydrates but may also include additional components and / or elements, such as those disclosed in this specification. Therefore, a "wood-derived carbohydrate composition" can be considered either a "wood-derived carbohydrate-containing composition" or a "wood-derived composition containing carbohydrates." The term "total dry matter content" can refer to the total amount of solids, including suspended solids and soluble or dissolved solids. Total dry matter content can be determined after removing the liquid from a sample, followed by drying at 45 °C for 24 hours. The effectiveness of the liquid removal can be verified by weighing the sample, drying it for an additional two hours at the specified temperature, and weighing it again. If the measured weights are substantially the same, the drying was complete and the total weight can be recorded. In one embodiment, the ratio of C5 monomeric sugars to C6 monomeric sugars in the carbohydrate composition is at most 0.1, or at most 0.05, or at most 0.03, or at most 0.015. In another embodiment, the ratio of C5 monomeric sugars to C6 monomeric sugars is from 0.015 to 0.15, or from 0.03 to 0.1, or from 0.03 to 0.05. The inventors have discovered, surprisingly, that by the process as disclosed in this specification, it is possible to produce a wood-derived carbohydrate composition comprising a high content of C6 monomeric sugars. Using the process described in this specification, C5 sugars can be efficiently removed from the carbohydrate composition. Soluble impurities can also be removed along with the C5 sugars. The separation of the liquid fraction and the fraction containing solid cellulose particles by a first solid-liquid separation process, which includes washing, in step ii) can reduce the amount of soluble sugars in CS by 80 to 95% by weight, or by 80 to 90% by weight, or by 85 to 90% by weight, relative to the amount present in the slurry. In one embodiment, the amount of sugars in CS is reduced by at least 80% by weight, or by at least 85% by weight, or by at least 90% by weight, or by at least 95% by weight, as a result of step ii). The amount of monomeric C5 sugars, monomeric C6 sugars, as well as the amount of oligomeric C5 sugars and oligomeric C6 sugars, can be determined both qualitatively and quantitatively by high-performance liquid chromatography (HPLC) by comparing them to standard samples. Examples of analytical methods can be found in, for example, Sluiter, A., et al., "Determination of sugars, byproducts, and degradation products in liquid fraction process samples," Technical Report, National Renewable Energy Laboratory, 2008, and Sluiter, A., et al., "Determination of Structural Carbohydrates and Lignin in Biomass," Technical Report, National Renewable Energy Laboratory, revised in 2012. In this document, all weight percentages are expressed as a percentage of the total dry matter content of the carbohydrate composition, unless otherwise stated. Similarly, other weight fractions (ppm, etc.) may also refer to a fraction of the total dry matter content of the carbohydrate composition, unless otherwise stated. The term "C5 sugars" shall be understood in this specification, unless otherwise specified, as meaning xylose, arabinose, or any mixture or combination thereof. The term "C6 sugars" shall be understood in this specification, unless otherwise specified, as meaning glucose, galactose, mannose, fructose, or any mixture or combination thereof. The term "monomeric sugar" shall be understood in this specification, unless otherwise specified, as a sugar molecule present as a monomer. that is, not coupled or linked to any other sugar molecule(s). In this specification, the quantities of various components / elements in the wood-derived carbohydrate composition are presented as percentages by weight relative to the total dry matter content of the carbohydrate composition. In this specification, the term "total dry matter content of the carbohydrate composition" may refer to the weight of the carbohydrate composition as determined after removing the liquid from the carbohydrate composition and then drying it at a temperature of 45 °C for 24 hours. The effectiveness of the liquid removal can be verified by weighing the sample, drying it for an additional two hours at the specified temperature, and weighing it again. If the measured weights are the same, the drying was complete and the total weight can be recorded. As is clear to those skilled in the art, the total quantity of the various components / elements in the composition of wood-derived carbohydrates cannot exceed 100% by weight. The percentage by weight of the various components / elements in the composition of wood-derived carbohydrates may vary within the given ranges. In one embodiment, the C5 monomeric sugars are xylose and / or arabinose. In another embodiment, the C6 monomeric sugars are glucose, galactose, and / or mannose. The carbohydrate composition may include C6 monomeric sugars and C5 monomeric sugars in a total amount of 80 to 95% by weight, or 82 to 94% by weight, or 85 to 93% by weight, or 90 to 92% by weight, as a percentage of the total dry matter content of the carbohydrate composition. In one embodiment, C6 monomeric sugars are present in an amount of at least 80% by weight, or at least 85% by weight, or at least 90% by weight, relative to the total dry matter content of the carbohydrate composition. In one embodiment, C5 monomeric sugars are present in an amount of at most 10% by weight, or at most 8% by weight, or at most 6% by weight, or at most 1% by weight, or at most 3% by weight relative to the total dry matter content of the carbohydrate composition. In one embodiment, C5 monomeric sugars are present in an amount of 1 to 10% by weight, or 1 to 8% by weight, or 1 to 6% by weight, or 1 to 4% by weight, or 1 to 3% by weight relative to the total dry matter content of the carbohydrate composition. The carbohydrate composition may include C6 oligomeric sugars and C5 oligomeric sugars in a total amount of 0.5 to 5% by weight, or 1 to 3% by weight, relative to the total dry matter content of the carbohydrate composition. The term "oligomeric" in this specification, unless otherwise stated, means a sugar molecule consisting of two monomers or more coupled or linked to each other. In one embodiment, the oligomeric C5 sugars are xylose and / or arabinose. In another embodiment, the carbohydrate composition does not include oligomeric C5 sugars. In another embodiment, the oligomeric C6 sugars are glucose, galactose, mannose, and / or fructose. The effectiveness of the washing performed in step ii) can be assessed by analyzing the liquid carbohydrate fraction to determine its composition quantitatively and / or qualitatively. This analysis can be used to determine, for example, the quantities and types of impurities present in the liquid carbohydrate fraction, as well as the absolute and relative amounts of C5 sugars and C6 sugars. Non-limiting examples of such a method for determining the presence of various impurities include, but are not limited to, conductivity, optical purity (e.g., color or turbidity), and the density of the liquid carbohydrate fraction. In one embodiment, the effectiveness of the washing performed in step ii) is evaluated by analyzing the fraction containing solid cellulose particles to determine the amount of soluble sugars present in that fraction. Non-limiting examples of such a method for determining the presence of various impurities include, but are not limited to, conductivity, optical clarity (e.g., color or turbidity), and the density of the liquid carbohydrate fraction. In one embodiment, the conductivity of a 10% aqueous solution of the carbohydrate composition is 0.5–10 mS / cm, or 0.5–5 mS / em, or 0.5–2 mS / cm, when determined according to SFS-EN 27888 (1994). The conductivity value can be used to determine the effectiveness of the washing that takes place in step ii). That is, the conductivity value can be used to determine the amount of soluble lignin present. In one embodiment, the ICUMSA color value of an aqueous solution of the carbohydrate composition is at most 20,000 IU, or at most 30,000 IU, or at most 40,000 TU, or at most 50,000 IU, when measured using a modified ICUMSA GS1 process without adjusting the pH of the sample to be analyzed and filtering the sample through a 0.45 jm filter prior to analysis. In one embodiment, the ICUMSA color value of an aqueous solution of the carbohydrate composition is 10,000 to 50,000 IU, 15,000 to 40,000 IU or 20,000 to 35,000 IU, when measured using a modified ICUMSA GS1 process without adjusting the pH of the sample to be analyzed and filtering the sample through a 0.45 µm filter prior to analysis. The carbohydrate composition may include organic and / or inorganic impurities (including soluble lignin) in an amount of up to 20% by weight, or not more than 12% by weight, or not more than 10% by weight, or not more than 8% by weight, or not more than 5% by weight, or not more than 3% by weight, or not more than 2% by weight, relative to the total dry matter content of the carbohydrate composition. The carbohydrate composition may include organic and / or inorganic impurities (including lignin) in an amount of 2 to 20% by weight, or 3 to 15% by weight, or 4 to 10% by weight, or 5 to 8% by weight, relative to the total dry matter content of the carbohydrate composition. The carbohydrate composition may include organic impurities in an amount of 1 to 9% by weight, or 2 to 8% by weight, or 3 to 7% by weight, relative to the total dry matter content of the carbohydrate composition. The carbohydrate composition may include inorganic impurities in an amount of 0.05–2% by weight, or 0.1–1.5% by weight, or 0.2–1% by weight, relative to the total dry matter content of the carbohydrate composition. Organic acids can be mentioned as examples of organic impurities. Non-limiting examples of organic impurities include oxalic acid, citric acid, succinic acid, formic acid, acetic acid, levulinic acid, 2-furoic acid, 5-hydroxymethylfurfural (S-HMF), furfural, glycolaldehyde, glyceraldehyde, as well as various acetates, formates, and other salts or esters. The quality and quantity of organic impurities in carbohydrate composition can be determined using, for example, HPLC coupled with a suitable detector, infrared (IR) spectroscopy, ultraviolet-visible (UV-VIS) spectroscopy, or nuclear magnetic resonance (NMR) spectrometry. Examples of organic impurities that may be present in carbohydrate composition are listed in Table 1 below. [Table 1] {fablisau !. Organic impurities and their quantity is Inorganic impurities can be salts from the group of elements consisting of Al, As, B, Ca, Cd, Cl, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Pb, S, Se, Si, and Zn. The quantities of inorganic impurities in the composition of carbohydrates can be analyzed using inductively coupled plasma optical emission spectroscopy (ICP-OES) in accordance with SFS-EN ISO 11885:2009. Examples of organic impurities that may be present in the composition of carbohydrates are listed in Table 2 below. [Tables 2] [Table 2. Inorganic Impurities and their quantities] In one embodiment, the carbohydrate composition comprises sulfur in an amount of 0.01 to 0.3% by weight, or 0.02 to 0.2% by weight, or 0.03 to 0.1% by weight, relative to the total dry matter content of the carbohydrate composition. The amount of sulfur can be determined in accordance with SFS-EN ISO 11885 (2009). The carbohydrate composition may include nitrogen in an amount of not more than 0.5%, or not more than 0.3% by weight, or not more than 0.25% by weight, or not more than 0.2% by weight, or not more than 0.15% by weight, relative to the total dry matter content of The carbohydrate composition, when measured as the total nitrogen content of the carbohydrate composition, may contain nitrogen in an amount of 0.01 to 1.0% by weight, or 0.03 to 0.75% by weight, or 0.05 to 0.5% by weight, relative to the total dry matter content of the carbohydrate composition, when measured as the total nitrogen content of the carbohydrate composition. The total amount of nitrogen present in the carbohydrate composition may be determined using any suitable method known to those skilled in the art, for example, the Kjeldahl method or catalytic thermal decomposition / chemioluminescence processes. The carbohydrate composition may include soluble lignin in an amount of not more than 5% by weight, or not more than 3% by weight, or not more than 1.5% by weight, or not more than 1% by weight, relative to the total dry matter content of the carbohydrate composition. The carbohydrate composition may include soluble lignin in an amount of 0.5 to 5% by weight, or 0.5 to 3% by weight, or 0.5 to 2% by weight, relative to the total dry matter content of the carbohydrate composition. The presence of soluble lignin in the carbohydrate composition may prove that the carbohydrate composition is derived from wood. The amount of soluble lignin can be determined by UV-VIS absorption spectroscopy as follows: the amount of soluble lignin present in the carbohydrate composition is determined by diluting a sample of carbohydrate composition so that its absorbance at 205 nm is 0.2 to 0.7 AU relative to a pure water reference sample, using a cuvette with a path length of 1 cm. The soluble lignin content of the sample in mg / L can then be calculated using the following equation. [Math.1] x=(4)xD where A is the absorbance of the sample, a is the absorption coefficient 0.110 / mgem, and D is a dilution factor. The total dry matter content of the wood-derived carbohydrate composition can be 5 to 15% by weight, or 6 to 13% by weight, or 7 to 11% by weight when determined after drying at a temperature of 45°C for 24 hours. The process for producing the wood-derived carbohydrate composition may include subjecting a wood-based feed to a pretreatment. For the purposes of this specification, "pretreatment" means, unless otherwise specified, (a) the process(es) carried out to convert the wood-based feed into a slurry. The slurry may be separated into a fraction comprising solid cellulose particles and a liquid fraction. The fraction comprising solid cellulose particles may also include a quantity of lignocellulose particles as well as free lignin particles. Lignocellulose comprises lignin chemically bonded to the cellulose particles. The wood-based raw material can be selected from a group consisting of hardwoods, softwoods, and combinations thereof. For example, the wood-based raw material may be pine, poplar, beech, aspen, spruce, eucalyptus, ash, or birch. It may also be any combination or mixture of these. The wood-based raw material may be hardwood. Preferably, hardwood is used due to its relatively high inherent sugar content, but the use of other types of wood is not excluded. Hardwood may be selected from a group consisting of beech, birch, ash, oak, maple, chestnut, willow, poplar, and any combination or mixture thereof. In one embodiment, the wood-derived carbohydrate composition is a hardwood-derived carbohydrate composition. Therefore, the wood-derived carbohydrate composition can be produced from wood, such as hardwood, hardwood, softwood, etc. In general, wood and wood-based raw materials are primarily composed of cellulose, hemicellulose, lignin, and extractives. Cellulose is a polysaccharide made up of a chain of glucose units. Hemicellulose includes polysaccharides such as xylan, mannan, and glucan. The supply of the wood-based feed charge in step 1) may include submitting the wood-based raw material to a mechanical treatment selected from debarking, chipping, splitting, cutting, beating, grinding, crushing, splitting, screening and / or washing of the wood-based raw material to form the wood-based feed charge. Thus, the supply of wood-based feed from wood-based raw material may include subjecting the wood-based raw material to mechanical processing to form wood-based feed. Mechanical processing may include debarking, chipping, splitting, cutting, beating, grinding, crushing, slitting, screening, and / or washing the wood-based raw material. During mechanical processing, wood chips may be debarked and / or wood chips of specified size and structure may be formed. The formed wood chips may also be washed, for example with water, to remove sand, gravel, and stones. In addition, the structure of the wood chips may be loosened before the pretreatment stage. The wood-based feed may contain a certain amount of bark from the logs of wood. The supply of wood-based feed may include the purchase of wood-based feed. Purchased wood-based feed may include wood chips or sawdust derived from a wood-based raw material. The pretreatment in step 1) of the wood-based feedstock may include one or more different pretreatment steps. During the different pretreatment steps, the wood-based feedstock itself changes. The objective of the pretreatment step(s) is to form a slurry for further processing. Pretreatment i) may include subjecting the wood-based feed to pre-steaming. Pretreatment ii) may include subjecting the wood-based feed, after mechanical treatment, to pre-steaming. Pretreatment in i) may include, before impregnation treatment, subjecting the wood-based feed to pre-steaming to form a pre-steamed wood-based feed. Pretreatment in i) may include impregnation treatment and steam blasting treatment, and may include, before impregnating and then steam blasting the wood-based feed, subjecting it to pre-steaming. Pre-steaming of the wood-based feed may be carried out with steam having a temperature of 100 to 130 °C at atmospheric pressure.During pre-steaming, the wood-based feedstock is treated with low-pressure steam. Pre-steaming can also be carried out with steam at temperatures below 100°C, 98°C, or 95°C. Pre-steaming has the added benefit of reducing or removing air from within the wood-based feedstock. Pre-steaming can take place in at least one pre-steaming reactor. Furthermore, pretreatment step (i) may include subjecting the wood-based feed material to at least one impregnation treatment to form an impregnated wood-based feedstock. The pretreatment step (i) may include subjecting the wood-based feedstock to at least one impregnation treatment with an impregnation liquid. The impregnation treatment may be carried out on the wood-based feedstock as received from mechanical processing and / or pre-steaming. The impregnation liquid may be selected from water, at least one acid, at least one alkali, at least one alcohol, or any combination or mixture thereof. The wood-based feed load can be transferred from mechanical processing and / or from pre-steaming to impregnation treatment using a feeding device. The feeder can be a screw feeder, such as a screw feeder. The feeder can compress the wood-based feed material during transfer. When the wood-based feed material then enters the impregnation treatment, it can expand and absorb the impregnation liquid. The impregnation liquid may comprise water, at least one acid, at least one alkali, at least one alcohol, or any combination or mixture thereof. The at least one acid may be selected from a group consisting of inorganic acids, such as sulfuric acid (H₂SO₄), nitric acid, and phosphoric acid; organic acids, such as acetic acid, lactic acid, formic acid, and carbonic acid; and any combination or mixture thereof. In one embodiment, the impregnation liquid comprises sulfuric acid, for example, dilute sulfuric acid. The concentration of the acid may be 0.3–5.0% w / w, 0.5–3.0% w / w, 0.6–2.5% w / w, 0.7–1.9% w / w, or 1.0–1.6% w / w. The impregnation liquid can act as a catalyst in driving the hydrolysis of hemicellulose in the wood-based feed charge.In one embodiment, impregnation is carried out using only water, i.e., by autohydrolysis. In another embodiment, the wood-based feedstock can be impregnated by alkaline hydrolysis. NaAOH and Ca(OH)₂ can be mentioned as examples to be used as alkali in alkaline hydrolysis. The impregnation treatment can be carried out in at least one impregnation reactor or tank. In one embodiment, two or more impregnation reactors are used. Transfer from one impregnation reactor to another can be accomplished using a screw feeder. The impregnation process can be carried out by conveying the wood-based feed through at least one impregnation reactor that is at least partially filled with the impregnation liquid. In other words, the wood-based feed can be transferred into the impregnation reactor, where it is immersed in the liquid, and then transferred out of the reactor so that the wood-based feed is homogeneously impregnated with the liquid. The result of the impregnation process is the formation of an impregnated wood-based feed. The impregnation process can be carried out in batches or continuously. The residence time of the wood-based feed in an impregnation reactor, that is, the time the wood-based feed is in contact with the impregnation liquid, can be from 5 seconds to 5 minutes, or 0.5 to 3 minutes, or approximately 1 minute. The temperature of the impregnation liquid can be, for example, from 20 to 99 °C, or from 40 to 95 °C, or from 60 to 93 °C. Maintaining the Impregnation liquid temperature below 100 °C has the added benefit of preventing or reducing the dissolution of hemicellulose. After the impregnation treatment, the impregnated wood-based feed can be left in, for example, a storage tank or silo for a predetermined period of time to allow the impregnation liquid absorbed into the wood-based feed to stabilize. This predetermined period can be from 15 to 60 minutes, or for example, approximately 30 minutes. In one embodiment, the wood-based feed charge is subjected to an impregnation treatment with dilute sulfuric acid having a concentration of 1.32% w / w and a temperature of 92°C. Pretreatment (i) may include subjecting the wood-based feed to steam blast treatment. The wood-based feed resulting from the impregnation treatment may be subjected to steam blast treatment. That is, pretreatment (i) may include subjecting the impregnated wood-based feed to steam blast treatment to form a steam-treated wood-based feed. In one embodiment, the pretreatment in (i) comprises the mechanical processing of the wood-based material to form a wood-based feed, the pre-steaming of the wood-based feed to form a pre-steamed feed, the impregnation treatment of the pre-steamed wood-based feed to form an impregnated wood-based feed, and the steam blasting treatment of the impregnated wood-based feed.In one embodiment, the pretreatment in i) comprises the impregnation treatment of the wood-based feedstock and the steam blast treatment of the impregnated wood-based feedstock. That is to say, the wood-based feedstock that has undergone the impregnation treatment can then undergo the steam blast treatment. Similarly, the wood-based feedstock that has undergone a pre-steaming treatment can then undergo the impregnation treatment, and the impregnated wood-based feedstock that has undergone the impregnation treatment can undergo the steam blast treatment. The wood-based feed can be stored in chip bins or silos, for example, between different processing stages. Alternatively, the feed Wood-based feed can be transported continuously from one treatment to another. The pretreatment in 1) may include step iib) of subjecting the impregnated wood-based feed to an explosion treatment, which is carried out by treating the impregnated wood-based feed with steam having a temperature of 130 to 240 °C, under a pressure of 0.17 to 3.25 MPaG, followed by a sudden explosive decompression of the feed. The feed may be steam-treated for 1 to 20 minutes, or 2 to 16 minutes, or 4 to 13 minutes, or 3 to 10 minutes, or 3 to 8 minutes, before the sudden explosive decompression of the steam-treated wood-based feed. In this specification, the term "steam explosion treatment" may refer to a hemihydrolysis process in which the feed is treated in a reactor (steam explosion reactor) with steam having a temperature of 130 to 240 °C, under a pressure of 0.17 to 3.25 MPaG, followed by a sudden explosive decompression of the feed which causes the fibrous structure of the feed to rupture. In one embodiment, the amount of sulfuric acid in the steam explosion treatment can be from 0.10 to 0.75% by weight relative to the total dry matter content of the wood-based feedstock. The amount of acid present in the steam explosion treatment can be determined by measuring the sulfur content of the liquid portion of the steam-treated wood-based feedstock or of the liquid portion of the steam-treated wood-based feedstock after the steam explosion treatment. The amount of sulfuric acid in the steam explosion reactor can be determined by subtracting the amount of sulfur in the wood-based feedstock from the measured amount of total sulfur in the steam-treated wood-based feedstock. Steam explosion treatment can be carried out in a pressurized reactor. This treatment involves treating the impregnated wood-based feed with steam at a temperature of 130 to 240 °C, under a pressure of 0.17 to 3.25 MPaG, followed by a sudden explosive decompression of the feed. The impregnated wood-based feed can be introduced into the pressurized reactor using a compression conveyor, such as a screw feeder. During transport with the screw feeder, if used, the acid in liquid form is removed, and some of the impregnation liquid absorbed by the feed is removed as pressurization, while the majority remains in the feed. The impregnated wood-based feed can be introduced into the pressurized reactor with steam and / or gas.The pressure in the pressurized reactor can be controlled by adding steam. The pressurized reactor can operate continuously or in batches. The load. Impregnated wood-based feed, for example, wood-based feed that has undergone an impregnation treatment, can be introduced into the pressurized reactor at a temperature of 25 to 140°C. The residence time of the feed in the pressurized reactor can be from 0.5 to 120 minutes. The term "residence time" in this specification should be understood, unless otherwise specified, as the time between the introduction or entry of the feed, for example, into the pressurized reactor, and its exit or discharge from the reactor. Following the hemihydrolysis of the wood-based feedstock affected by steam explosion treatment in the reactor, the hemicellulose present in the wood-based feedstock can be hydrolyzed or degraded into oligomers and / or monomers of xylose, for example. Hemicellulose comprises polysaccharides such as xylan, mannan, and glucan. The xylan is thus hydrolyzed into xylose, which is a monosaccharide. In one embodiment, the conversion of the xylan present in the feedstock to xylose following hemihydrolysis is 87–95%, 89–93%, or 90–92%. Thus, the steam explosion of the feedstock can result in the formation of a steam-treated wood-based feedstock. The steam-treated wood-based feedstock resulting from the steam explosion can be subjected to steam separation. The steam-treated wood-based feedstock resulting from the steam explosion treatment can be mixed or combined with a liquid, for example, water. The steam-treated wood-based feedstock resulting from the steam explosion treatment can be mixed with a liquid to form a slurry. The liquid can be pure water or water containing CS sugars. The water containing C5 sugars can be recycled water from the separation and / or washing of the fraction containing solid cellulose particles prior to enzymatic hydrolysis.The steam-treated wood-based feed can be mixed with the liquid, and the resulting mass can be mechanically homogenized to break up any agglomerates. The pretreatment in (i) may include mixing the steam-treated wood-based feed with a liquid. Following pretreatment 1), a slurry can be formed. The slurry may comprise a liquid phase and a solid phase. The slurry may contain solid cellulose particles. In step ii), the slurry can be separated into a liquid fraction and a fraction containing solid cellulose particles. The process comprises ii) the separation of a liquid fraction and a fraction comprising solid cellulose particles by a first solid-liquid separation process wherein the first solid-liquid separation process includes a washing. In one embodiment, the washing in ii) is continued until the The quantity of soluble organic components in the fraction comprising solid cellulose particles is either 0.5 to 5% by weight, or 1 to 4% by weight, or 1.5 to 3% by weight relative to the total dry matter content. In one embodiment, the washing in step ii) is continued until the quantity of soluble organic components in the fraction comprising solid cellulose particles is 0.5 to 5% by weight, or 1 to 4% by weight, or 1.5 to 3% by weight relative to the total dry matter content of the fraction comprising solid cellulose particles. In one embodiment, a fraction comprising solid cellulose particles having a total dry matter content of 15 to 50% by weight, or 21 to 40% by weight, or 25 to 40% by weight, or 30 to 40% by weight, or 35 to 40% by weight is formed in ii). In one embodiment, the first solid-liquid separation process of step ii) is carried out by displacement washing or countercurrent washing. Thus, the first solid-liquid separation process can be chosen from displacement washing and countercurrent washing. Displacement washing, also known as replacement washing, is a process for separating solids and liquids using a relatively small amount of washing liquid. Thus, displacement washing can be considered an operation by which solid particles can be washed with a minimal quantity of washing liquid, such as water. In countercurrent washing, the movement of the fraction containing solid cellulose particles is generally forward, while the wash liquid, such as water, flows in the opposite direction. As with displacement washing, countercurrent washing can also significantly reduce wash liquid consumption. In one embodiment, the countercurrent washing process comprises at least two solid-liquid separation steps and a dilution between steps with a washing solution. The washing solution may be clean water. The amount of water required may vary depending on the total number of solid-liquid separation steps performed, the total dry matter content of the feed to the solid-liquid separation step, and the total dry matter content of the fraction containing solid cellulose particles after each solid-liquid separation step. The washing fluid can be fresh or recycled. It can be soft water, potable water, or a low-sugar liquid. The conductivity of the washing fluid can be approximately 0.1 mS / em. The ratio of used washing liquid to solids in step 11) can be from 0.5:1 to 8:1 (w / w), or from 0.5:1 to 5:1 (w / w), or from 0.5:1 to 3:1 (w / w), or from 0.5:1 to 2:1 (w / w) in the case of a wash by displacement. The progress of both displacement and countercurrent washing can be monitored by measuring the conductivity of the liquid fraction recovered from this treatment. When the conductivity of the liquid fraction is less than or equal to a predetermined threshold value of 0.35 mS / cm, it can be concluded that the desired amount of CS sugars and other soluble impurities has been removed and the washing can be terminated. In one embodiment, the washing is continued until the conductivity of the liquid fraction is 0.1 to 1.0 mS / cm or 0.2 to 0.5 mS / cm. Following step ii), a fraction comprising solid cellulose particles having a total dry matter content of 15 to 50% by weight is formed. The inventors made a surprising discovery: by separating the liquid fraction and the fraction containing solid cellulose particles from each other using the first solid-liquid separation process, for example, by displacement washing or countercurrent washing, the amount of sugars in solid cellulose particles was beneficially reduced, thus significantly affecting the outcome of the process, i.e., the properties of the carbohydrate composition. The process described in this specification has the added advantage of yielding a high-quality or high-purity carbohydrate composition for use in other applications. The separated liquid fraction may therefore include C5 sugars from hydrolyzed hemicellulose as well as soluble lignin and other by-products. The fraction containing solid cellulose particles may, in addition to cellulose, include lignin. Since C-segmented sugars are efficiently removed with the liquid fraction, the fraction containing solid cellulose particles may include carbohydrates such as solid C6 sugars. The fraction containing solid cellulose particles may also include other carbohydrates and other components. The fraction containing solid cellulose particles may also include some C5 sugars. The separated and recovered fraction comprising solid cellulose particles can be further purified or washed before being subjected to enzymatic hydrolysis. In one embodiment, the separated fraction comprising solid cellulose particles is diluted in step iii) to a total dry matter content of 8–20% by weight, or 10–18% by weight, or 15–16% by weight. Thus, if necessary, the separated fraction comprising solid cellulose particles is diluted in step iii). The need for dilution depends on the total dry matter content that the fraction comprising solid cellulose particles may have as a result of step ii). That is, if the total dry matter content of the fraction comprising solid cellulose particles as a result of step ii) is greater than 20% by weight, The fraction containing solid cellulose particles can then be diluted. If the total dry matter content of the fraction containing solid cellulose particles as a result of step ii) is between 8 and 20% by weight, then no dilution is necessary. The fraction containing solid cellulose particles can be diluted with water and / or another liquid containing at least soluble carbohydrates. In one embodiment, the fraction containing solid cellulose particles can be diluted in step iii) with water to a total dry matter content of 8 to 20% by weight, or 10 to 18% by weight, or 15 to 16% by weight. In one embodiment, the separated fraction comprising solid cellulose particles is subjected to enzymatic hydrolysis to form a hydrolysis product, wherein the fraction comprising solid cellulose particles has a total dry matter content of 8 to 20% by weight when subjected to enzymatic hydrolysis. Step iv), which involves subjecting the fraction containing solid cellulose particles to enzymatic hydrolysis, can be carried out at a temperature of 30–70 °C, 35–65 °C, 40–60 °C, 42–59 °C, 45–58 °C, or 47–57 °C. Step iv) can also be carried out at atmospheric pressure. The pH of the fraction containing solid cellulose particles can be maintained during step iv) at a pH value of 3.5–6.5, 4.0–6.0, or 4.5–5.5. The pH of the fraction containing solid cellulose particles can be adjusted by adding an alkali and / or an acid. Step iv) of subjecting the fraction comprising solid cellulose particles to enzymatic hydrolysis can be continued for 20 to 120 h, or 30 to 90 h, or 40 to 80 h.The enzymatic hydrolysis of the fraction comprising solid cellulose particles can be carried out continuously, as a batch process, or as a combination of a continuous and a batch process. In one embodiment, enzymatic hydrolysis is carried out at a temperature of 30 to 70 °C, or 35 to 65 °C, or 40 to 60 °C, or 45 to 55 °C, or 48 to 53 °C, while maintaining the pH of the fraction comprising solid cellulose particles at a value of 3.5 to 6.5, or 4.0 to 6.0, or 4.5 to 5.5, and in which enzymatic hydrolysis is allowed to continue for 20 to 120 h, or 30 to 90 h, or 40 to 80 h. Enzymatic hydrolysis can be carried out in at least one step of the process. In one embodiment, enzymatic hydrolysis can be carried out as a one-step hydrolysis process, in which the fraction comprising solid cellulose particles is subjected to enzymatic hydrolysis in at least one first hydrolysis reactor. After hydrolysis, the hydrolysis product, i.e., the hydrolysate, can be subjected to separation, in which the solid fraction The fraction containing lignin, which in addition to lignin may also include unhydrolyzed cellulose, is separated from the liquid carbohydrate fraction. This one-step hydrolysis process can be carried out as a batch process, for example, using several reactors operating in parallel, in which each reactor can receive a portion of the fraction containing solid cellulose particles. Alternatively, separate parallel lines with parallel reactors can be used. In one embodiment, enzymatic hydrolysis can be carried out as a two-step hydrolysis process or as a multi-step hydrolysis process. In either the two-step or multi-step hydrolysis process, the fraction comprising solid cellulose particles can first undergo enzymatic hydrolysis in at least one first hydrolysis reactor. The resulting liquid carbohydrate fraction can then be separated from the solid fraction comprising lignin, which may also include unhydrolyzed cellulose. The solid fraction can then undergo a second or further enzymatic hydrolysis, for example, in at least one other hydrolysis reactor.At least one of the first and second or any other enzymatic hydrolysis steps may be carried out as a batch process or as a continuous process comprising, for example, one or more reactors operating in parallel. After the second or any other enzymatic hydrolysis step, the hydrolysis product, i.e., the hydrolysate, may be subjected to separation, in which the solid fraction comprising the lignin is separated from the liquid fraction of carbohydrates. The reaction time in the first hydrolysis reactor can be from 8 to 72 hours. The reaction time in the second and / or any last hydrolysis reactor can be from 8 to 72 hours. Enzymes are catalysts for enzymatic hydrolysis. The enzymatic reaction lowers the pH and, by shortening the length of the cellulose fibers, can also decrease viscosity. Subjecting the fraction containing solid cellulose particles to enzymatic hydrolysis can lead to the transformation of cellulose into glucose monomers by enzymes. The lignin present in the fraction containing solid cellulose particles can remain essentially in solid form. At least one enzyme can be used to carry out the enzymatic hydrolysis. This enzyme can be chosen from a group consisting of cellulases, hemicellulases, laccases, and lignolytic peroxidases. Cellulases are multiprotein complexes made up of synergistic enzymes with different specific activities, which can be divided into exo- and endo-cellulases (glucanase) and B- glucosidase (cellobiose). The enzymes can be commercially available mixtures of cellulases or manufactured on site. Cellulose is an insoluble linear polymer composed of repeating glucose units linked by 3-1-4-glucosidic bonds. During enzymatic hydrolysis, cellulose chains are broken by the breaking of at least one β-1-4-glucosidic bond. Enzymatic hydrolysis can lead to the formation of the hydrolysis product. In step v), the hydrolysis product can be separated into a solid fraction comprising lignin and a liquid fraction of carbohydrates by a second solid-liquid separation process to recover the liquid carbohydrate fraction as a wood-derived carbohydrate composition. During the separation in step v), the solid fraction can be separated from the liquid fraction. In one embodiment, step v) comprises the separation of the solid fraction, including lignin, from the liquid fraction, including carbohydrates, by a second solid-liquid separation process. The separation in step v) can be carried out by filtration, decantation, and / or centrifugation. Filtration can be vacuum filtration, filtration based on reduced pressure, filtration based on increased pressure, or a filter press effect. Decantation can be repeated to improve the separation. The liquid carbohydrate fraction recovered from enzymatic hydrolysis can be purified after step v). Purification of the liquid carbohydrate fraction can be carried out using at least one of the following processes: (membrane) filtration, crystallization, sterilization, pasteurization, evaporation, chromatography, ion exchange, flocculation, flotation, precipitation, centrifugal separation, microfiltration, ultrafiltration, nanofiltration, reverse osmosis, electrodialysis, heat treatment, activated carbon treatment, or any combination thereof. Purification of the liquid carbohydrate fraction has the added benefit of providing a desirable target quality of sugars. The process as disclosed in this specification has the added benefit of providing a wood-derived carbohydrate composition with a high content of C6 monomer sugars. This wood-derived carbohydrate composition also has the added benefit of meeting the purity requirements for subsequent use in, for example, a catalytic conversion process for the production of, for example, monoethylene glycol. Examples Reference will now be made in detail to the methods of implementation of this disclosure, an example of which is illustrated in the attached drawing. The description below presents certain embodiments in sufficient detail to enable a person skilled in the art to use the process based on the disclosure. Not all steps in the embodiments are discussed in detail, as many steps will be obvious to a person skilled in the art based on this disclosure. For simplicity, article numbers will be maintained in the following exemplary embodiments in the case of repetitive components. Figure 1 below illustrates a detailed embodiment of a flowchart of the process for producing a carbohydrate composition derived from hardwood. The process in Figure 1 for producing a carbohydrate composition derived from hardwood includes supplying a wood-based feedstock derived from a wood-based raw material and comprising wood chips, and subjecting the wood-based feedstock to a pretreatment to form a slurry (step i) of Figure 1). The slurry is then separated into a liquid fraction and a fraction comprising solid cellulose particles by a first solid-liquid separation process comprising a washing (step ii) of Figure 1). The separated fraction comprising solid cellulose particles is then optionally diluted (step iii) of the [Fig.1]). Next, the fraction containing solid cellulose particles is subjected to enzymatic hydrolysis to form a hydrolysis product (step iv) of [Fig. 1]. The hydrolysis product is then separated to form a solid fraction containing lignin and a liquid fraction of carbohydrates by a second solid-liquid separation process to recover the liquid carbohydrate fraction as a wood-derived carbohydrate composition (step v) of [Fig. 1]. Example | - Production of a carbohydrate composition derived from wood In this example, a wood-derived carbohydrate composition was prepared. First, a wood-based feed consisting of beech chips was provided. The wood-based feed was then subjected to pretreatment as follows: The wood-based feedstock underwent pre-steaming. This pre-steaming was carried out at atmospheric pressure with steam at a temperature of 100 °C for 180 minutes. The pre-steamed feedstock was then impregnated with dilute sulfuric acid at a concentration of 1.32% w / w and a temperature of 92 °C. The pre-steamed wood-based feedstock was allowed to be affected by the impregnation liquid for 30 minutes. The impregnated wood-based feedstock was then subjected to steam blasting. The steam explosion treatment was carried out by treating the impregnated wood-based feed with steam at a temperature of 191 °C at atmospheric pressure, followed by a sudden, explosive decompression of the wood-based feed. The amount of sulfuric acid in the steam explosion reactor was 0.33% by weight relative to the total dry matter content of the wood-based feed. To determine the amount of sulfuric acid, the sulfur content of the wood was 0.02% by weight relative to the total dry matter content of the wood used. During pretreatment, the conversion of xylan from the wood-based feed to xylose was 91%, and the ratio of solubilized glucose to solubilized xylose was 0.15, as determined by HPLC-RI. The steam-treated wood-based feed was then mixed with water in a mixing vessel. Following the pretreatment steps described above, a slurry was formed. The slurry comprised a liquid fraction and a fraction containing solid cellulose particles. The fraction containing solid cellulose particles contained lignin. The slurry was then separated into the liquid fraction and the fraction containing solid cellulose particles by a first solid-liquid separation process, which in this example was a backwash. The backwash was continued until the amount of soluble components in the fraction containing solid cellulose particles was 2.0% by weight relative to the total dry matter content. The total dry matter content of the fraction containing solid cellulose particles was 32% by weight after washing. The resulting fraction, comprising solid cellulose particles with a total dry matter content of 32% by weight, was diluted to a total dry matter content of approximately 13% by weight and then subjected to enzymatic hydrolysis in a batch reactor using the following conditions: initial pH = 5.0 adjusted with NaOH enzyme = commercially available mixture of cellulases Length of stay = 53 hours temperature = 47 - 52 °C during the process. The dosage of the cellulase mixture was chosen so that the glucose conversion after 53 hours was 83%. Enzymatic hydrolysis yielded a hydrolysis product. The hydrolysis product was then separated into a solid fraction comprising lignin and a liquid fraction of carbohydrates. These were separated from each other using a decanting centrifuge in a two-stage washing process. The carbohydrate concentration of the liquid fraction of carbohydrates was approximately 8% by weight during the first washing stage and approximately 4% by weight during the second washing stage, after re-slurrying. The liquid carbohydrate fraction was recovered as a wood-derived carbohydrate composition, which was analyzed by HPLC-RI using a Waters Alliance e2695 separation module, a Waters 2998 photodiode array, and a Waters 2414 refractive index detector. Separation was performed using a 300 mm x 7.8 mm Bio-Rad Aminex HPX-87 column equipped with Micro-Guard Deashing and Carbo-P guard columns in series. Ultrapure water was used as the eluent. The results are presented in the table below: [Tables 3] The amount of oligomeric sugars in the sample was determined by hydrolyzing the oligomeric sugars to monomeric sugars by acid hydrolysis, analyzing the acid-hydrolyzed sample by HPLC-RI, and comparing the result to those of samples for which hydrolysis was not performed. By subtracting the amount of monomeric sugars in the untreated sample, the amount of oligomeric sugars was calculated. It is obvious to a person skilled in the art that, with advances in technology, the basic idea can be implemented in various ways. The embodiments are therefore not limited to the examples described above; on the contrary, they can vary within the scope of the claims. The embodiments described above may be used in any combination with one another. Several embodiments may be combined to form an additional embodiment. A wood-derived carbohydrate composition or a process described in this document may include at least one of the embodiments described above. It will be understood that the advantages and benefits described above may relate to a single embodiment or to several embodiments. The embodiments are not limited to those that solve one or all of the stated problems or to those that offer one or all of the stated advantages and benefits. It will further be understood that a reference to "an element" refers to one or more of these elements.The term "including" is used in this specification to signify the inclusion of the feature(s) or act(s) which follows(s) afterwards, without excluding the presence of one or more additional features or acts.

Claims

Demands

1. Composition of wood-derived carbohydrates comprising sugars cn C6 monomers and sugars in C5 monomers in a total quantity of less than 80% by weight relative to the total dry matter content of the carbohydrate composition, in which the ratio of sugars to C5 monomers on the sugars in C6 monomers is at most 0.

15.

2. Wood-derived carbohydrate composition according to claim 1, in which has a carbohydrate composition comprising C6 sugars monomers and sugars in C5 monomers in a total quantity of 80 at 95% by weight, preferably 82 to 94% by weight, more preferably- typically from 85 to 93% by weight, even more preferably from 90 to 92% by weight, relative to the total dry matter content of the com- carbohydrate position.

3. Carbohydrate composition derived from wood according to any one of the re- previous demands, in which the carbohydrate composition includes C6 oligomeric sugars and C5 oligomeric sugars in a total quantity of 0.5–5% by weight, preferably 1–3% by weight, relative to the total dry matter content of the composition of carbohydrates.

4. Carbohydrate composition derived from wood according to any one of the re- previous claims, in which the ratio of sugars in C5 monomers on C6 sugars monomers in the composition of carbohydrates is 0.015 to 0.15, preferably 0.03 to 0.1, more preferably- tiellement from 0.03 to 0.

05.

5. Carbohydrate composition derived from wood according to any one of the re- previous demands, in which the carbohydrate composition includes soluble lignin in an amount of no more than 5% by weight, preferably not more than 3% by weight, more preferably not more than 1.5% by weight, or even more preferably, at most 1% by weight, relative to the total dry matter content of the composition of carbohydrates.

6. Carbohydrate composition derived from wood according to any one of the re- previous demands, in which the carbohydrate composition includes organic and / or inorganic impurities in a quantity not more than 20% by weight, preferably not more than 12% by weight, plus preferably of no more than 10% by weight, even more preferably- tiellement d'au plus $ % en weight, even more preferably d'au plus 5% by weight, or even more preferably by no more than 3% by weight, or even more preferably of no more than 2% by weight, reported to the total dry matter content of the carbohydrate composition.

7. Wood-derived carbohydrate composition according to any one of the re- previous demands, in which the composition includes sulfur in an amount of 0.01 - 0.3% by weight, preferably 0.02 - 0.2% by weight, more preferably 0.03–0.1% by weight, relative to the total dry matter content of the composition of carbohydrates.

8. Carbohydrate composition derived from wood according to any one of the re- previous demands, in which the carbohydrate composition includes nitrogen in an amount of 0.01 to 1.0% by weight, of preferably from 0.03 to 0.75% by weight, more preferably from 0.05 to 0.5% by weight, relative to the total dry matter content of the com- carbohydrate position when measured as total content nitrogen from the composition of carbohydrates.

9. Carbohydrate composition derived from wood according to any one of the re- previous claims, in which the sugars are C6 monomers are present in a quantity of at least 80% by weight, preferably of at least 85% by weight, more preferably of at least 90% by weight relative to the total dry matter content of the composition carbohydrates.

10. Carbohydrate composition derived from wood according to any one of the re- previous claims, in which the sugars are C5 monomers are present in a quantity of no more than 10% by weight, preferably of at most 8% by weight, more preferably of at most 6% by weight, even more preferentially of at most 4% by weight, even more pre- by reference to no more than 3% by weight relative to the total content of dry matter of the carbohydrate composition.

11. | Carbohydrate composition derived from wood according to any one of the re- previous claims, in which the conductivity of a solution The aqueous concentration at 10% of the carbohydrate composition is 0.5 to 10 mS / cm, of preferably from 0.5 to 5 mS / cm, more preferably from 0.5 to 2 mS / cm, when it is determined according to the SFS-EN 27888 standard.

12. Carbohydrate composition derived from wood according to any one of the re- previous claims, in which the ICUMSA color value The composition of an aqueous solution of carbohydrates is 10,000 to 50 000 IU, preferably from 15,000 to 40,000 TU, more preferably from 20,000 to 35,000 IU.

13. A process for producing a wood-derived carbohydrate composition, in which the process includes:

1. the supply of a wood-based feed load derived from a wood-based raw material and including wood chips, and the act of submitting the wood-based feedstock with pretreatment for to form a slip: it. the separation of the slip into a liquid fraction and a fraction comprising solid cellulose particles by a first solid-liquid separation process to form a fraction comprising solid cellulose particles having a total dry matter content of 15 to 50% weight, in which the first solid- separation process liquid includes washing the fraction comprising solid cellulose particles until the amount of soluble organic components in the fraction comprising solid cellulose particles, representing 0.5 to 5% by weight relative to the total dry matter content; Optionally, the dilution of the separated fraction comprising solid cellulose particles up to a total content of dry matter of 8 to 20% by weight; iv. the act of submitting the fraction comprising particles of solid cellulose undergoes enzymatic hydrolysis to form a hydrolysis product, in which the fraction comprising solid cellulose particles have a total content of dry matter content of 8 to 20% by weight; and v. the separation of the hydrolysis product into a solid fraction comprising lignin and a liquid fraction of carbohydrates by a second solid-liquid separation process for recover the liquid fraction of carbohydrates as com- position of carbohydrates derived from wood.

14. The method of claim 13, wherein the pretreatment in i) includes subjecting the wood-based feed load to at least one impregnation treatment to form a filler impregnated wood-based food.

15. The method of claim 14, wherein the pretreatment in i) includes subjecting the feed load to wood-based impregnated with a steam explosion treatment to form a steam-treated wood-based feed charge.

16. The method of claim 15, wherein the pretreatment in i) includes the mixture of treated wood-based feed charge steam with a liquid.

17. A method according to any one of claims 13 to 16, wherein The pretreatment in 1) includes, before submitting to treatment impregnation, to subject the wood-based feed load to a pre-steaming process to create a wood-based feed load pre-stewed.

18. A method according to any one of claims 13-17, wherein the first solid-liquid separation process in ii) is carried out by a Displacement washing or counter-current washing.

19. A method according to any one of claims 13 to 18, wherein the washing in ii) is continued until the quantity of components soluble organic matter in the fraction comprising particles of solid cellulose, either 1 to 4% by weight, preferably 1.5 to 3% by weight weight relative to the total dry matter content.

20. A method according to any one of claims 13 to 19, wherein a fraction comprising solid cellulose particles having a total dry matter content of 21-40% by weight, preferably of 25-40% by weight, more preferably 30-40% by weight, even more preferably 35-40% by weight is formed in ii).

21. | Method according to any one of claims 13 to 20, wherein the separated fraction comprising solid cellulose particles is diluted in iii) up to a total dry matter content of 10 to 18% in weight, preferably 15 to 16% by weight.

22. A method according to any one of claims 13 to 21, wherein Enzymatic hydrolysis is carried out at a temperature of 30 to 70 °C. preferably from 35 to 65 °C, more preferably from 40 to 60 °C, even more preferentially from 42 to 59 °C, even more preferentially- typically from 45 to 58 °C, even more preferentially from 47 to 57 °C while maintaining the pH of the fraction containing particles of cellulose solids at a pH value of 3.5 - 6.5, preferably 4.0 - 6.0, more preferably 4.5 - 5.5, and in which we leave Enzymatic hydrolysis continues for 20-120 hours, from preferably 30–90 h, more preferably 40–80 h.

23. Wood-derived carbohydrate composition obtainable by the process as defined in any one of claims 13 to 22.

24. Wood-derived carbohydrate composition according to claim 23, in which the carbohydrate composition derived from wood is such that defined in any one of claims 1 to 12.

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